Previously, the most widely used approach for transmitting a first format data on a redundant second format was to use a network hub with two links connected to another network hub. However, translation via each data hub port introduces significant data delays, typically in excess of 90 serial data bits, which reduces the network performance and adds to the limitations of the physical size of the network.
Such data delay and other data translation limitations experienced by hub and other prior data translation devices are, in large part, a result of internal transfer data from the incoming media serial format to an internal parallel format for buffering or processing, and back to the serial format for retransmission. The well established building blocks used in many such systems consist of a an integrated circuit, e.g. part #DP83223, which provides the necessary electrical signalling and media state, while a second subsequently connected integrated circuit, e.g. part #DP83240, recovers the clock signal from the incoming signal, decodes or descrambles the NRZ, MLT3 or other cipher format encrypted signal and provides a plaintext data signal in a 4-bit parallel standard. The plaintext parallel data is then received by a buffer or processor provided by a variety of integrated circuits as are known in the art. For hub configurations, similar parallel data paths are provided.
Additional data delays or system complexities arise for system accommodation of data path failure detection and redundant path switchover in the event of master (primary) data path failures. Moreover, in view of the extended delay in data transmissions and path switchover, significant data will be lost before the redundant (secondary or slave) data paths are connected or enabled.
As demonstrated by the widespread adherence to the parallel data format by integrated circuit and equipment designers, the above-discussed limitations imposed on the data flow are generally accepted as unavoidable, and thus the performance of redundant path data translation equipment is marginal.